Method for fabricating semiconductor device having fin structure that includes dummy fins

Abstract

A method for fabricating semiconductor device is disclosed. First, a substrate, and a sacrificial mandrel is formed on the substrate, in which the sacrificial mandrel includes a first side and a second side with the indentation. Next, a spacer is formed adjacent to the first side and the second side of the sacrificial mandrel, the sacrificial mandrel is removed, and the spacer is used to remove part of the substrate for forming a fin-shaped structure and a dummy fin-shaped structure.

What is claimed is: 
     
       1. A method for fabricating semiconductor device, comprising:
 providing a substrate; 
 forming a sacrificial mandrel on the substrate, wherein the sacrificial mandrel comprises an indentation; and 
 forming a spacer adjacent to the sacrificial mandrel. 
 
     
     
       2. The method of  claim 1 , wherein the sacrificial mandrel comprises a first side and a second side with the indentation, the method further comprises;
 forming the spacer adjacent to the first side and the second side; 
 removing the sacrificial mandrel; and 
 using the spacer to remove part of the substrate for forming a fin-shaped structure and a dummy fin-shaped structure. 
 
     
     
       3. The method of  claim 2 , wherein the dummy fin-shaped structure comprises a curve. 
     
     
       4. The method of  claim 3 , wherein the curve is omega shaped. 
     
     
       5. The method of  claim 2  further comprising:
 performing a fin-cut process; 
 forming a gate structure on the fin-shaped structure; 
 forming a first epitaxial layer on the fin-shaped structure adjacent to two sides of the gate structure and a second epitaxial layer on the dummy fin-shaped structure; and 
 forming a contact plug on the first epitaxial layer and the second epitaxial layer. 
 
     
     
       6. The method of  claim 5 , further comprising:
 forming a silicide on the first epitaxial layer and the second epitaxial layer; and 
 forming the contact plug on the silicide.